1. Field of Invention
The present invention relates to a liquid crystal display device and an electronic apparatus. More specifically, the invention relates to obtaining a display having a high contrast and a wide viewing angle in a transflective liquid crystal display device in which display is performed in both a reflective mode and a transmissive mode.
2. Description of Related Art
A related art liquid crystal display device includes a transflective liquid crystal display device that provides a display that is visible using external light, similarly to a reflective liquid crystal display device, in a bright place. The transflective liquid crystal display device also provides a display that uses a backlight, similarly to the transmissive liquid crystal display device, in a dark place. Such a related art transflective liquid crystal display device includes a liquid crystal display device in which a liquid crystal layer is interposed between an upper substrate and a lower substrate, a reflective film obtained by forming windows to transmit light in a metal film made of, for example, aluminum is provided on the inner face of a lower substrate, and the reflective film is then allowed to serve as a transflective plate. In this case, in the reflective mode, the external light incident from the upper substrate side passes through the liquid crystal layer, is reflected by the reflective film at the inner surface of the lower substrate, passes through the liquid crystal layer again, and is emitted from the upper substrate side, thereby contributing to the display. On the other hand, in the transmissive mode, light from a backlight incident from the lower substrate side passes through the liquid crystal layer from the windows of the reflective film and is emitted from the upper substrate side to the outside, thereby contributing to the display. Therefore, the area in which the windows are formed in an area in which the reflective film is formed become the transmissive display region, and the areas other than transmissive display region become the reflective display region.
However, the related art transflective liquid crystal display device is subject to a problem in that the viewing angle in the transmissive display is narrow. This is because a transflective plate is provided at an inner surface of a liquid crystal cell so as not to generate parallaxes, and thus there is a restriction that the reflective display should be performed using only one polarizer provided on the observer side. Therefore, the degree of freedom in the optical design is small. Therefore, in order to address or solve the above problem, a related art liquid crystal display device uses a vertically aligned liquid crystal, which is disclosed in “Development of transflective LCD for high contrast and wide viewing angle by using homeotropic alignment”, M. Jisaki et al., Asia Display/IDW'01, pp. 133–136 (2001), (hereinafter “Jisaki et al.). Three features thereof are as follows:
(1) A “VA (Vertical Alignment) mode” is employed in which a liquid crystal with a negative dielectric anisotropy is aligned vertically at the substrate, and then it falls down by applying a voltage.
(2) A “multi-gap structure” is employed in which the thicknesses of the liquid crystal layer in the transmissive display region and the reflective display region are different from each other (for this feature, see, for example, Japanese Unexamined Patent Application Publication No. 11-242226.
(3) The transmissive display regions are formed as regular octagons, and protrusions are provided at the centers of the transmissive display region on the counter substrate such that the liquid crystal molecules fall down in eight directions in those areas. That is, a so-called “alignment division structure” is employed.